Crank arm



CQH. FISH.

CRANK ARM. "APPLICATION FILED APR. 7, 1921.

1,428,366; PatentedSept.5,1922.

Patented Sept. 5, 1922.

entrain CHARLES 1'1. FISH, 01'" RYE, NEW HAMPSHIRE.

- CRANK ARM.

Application filed s in 7, 1921. serau no. 459,340..

To all whom it may concern:

Be it known that 1, CHARLES H. FISH, a citizen of-the United States, residing at Eye, in the county of Rockingham and State or New Hampshire, have invented certain new and useful'lmprovements in a Crank Arm, of which the following is a specification.

This invention relates to crank arms, and is particularly concerned with crank arms intended to oscillate the lay of a loom;

It is the chief object of the invention to devise'a crank arm construction which can be manufacturedeconomically, which will be light in weight, Which will have substantially greater length of life than the crank arms commonly used, which will eliminate the difliculties experienced-in prior constructions in properly lubricating the bearing surfaces, and in which the wearing parts can be economically renewed; I I

The nature of the invention will. be readily understood from the following description when read in connection with the accompanying drawings, and the novel features will be particularly pointed out in the appended claims.

Referring now to the drawings,

Figure 1 is a side elevation of a crank construction embodying the invention;

Fig. 2 is an'edge view of the construction shown in Fig. 1;

Fig. 3 is a side elevation of a modified construction; and i Fig. 4 is a crosssectional view on the line 4 4:, Fig. 3.

Referring first'to Figs. 1 and 2, the construction there shown comprises an arm 2,

preferably, although not necessarily, made of wood, this arm having a 'V-shaped gro' ve 3 cut in the left-hand end thereof, and also having flat shoulders -1- lat the opposite.

sides of said groove. For convenience in sawing this groove a hole/5 p'referably'is bored through the arm at the apex of'the groove and the sawing or'cutting operations are then performed;

Seated in the groove 3 is a bearing block 6 which may be either of the solid or split type, the latter type being shown, this block having a hole 7 formed therethrough to re oeive a crank pin, wrist pin, or the like. The block is held on the end of the arm 2 by a strap 8 ofapproximately U-shape which fitsover the end of thebearing block and'extends back along opposite sides of the arm 2 where it is secured to the arm by two bolts M 9 and. 10. Thebolt 10 extends simply through the strap 8 and arm 2, but the bolt 9 is located in a hole, the axis, of which lies substantially in'the plane of the. shoulders,

d d. That is, this hole is formed partly in the end surfaceof thearr'ciQ andpartly in the lower portion of thebearing block 6. It

will be observed that 'the'groove 3 extends n a'direction parallel to the axis of the bear-' ng surface 7, and this interlocking relationship of the bearingjblock and the arm 2 prevents relative lateral movement between these parts ina direction at right angles to said axis, wlfile'the bolt 9 prevents relative lateral .movement between these parts in a direction parallel'to saidaxis. This construction therefore secures the block firmly to the end of thecr'ank arm.

lVhile the bearing block 6 may be made of.

any'su'itab'le material, I'prefer to make it of wood which has been treated in some manner to render it self-lubricating, and I have found that remarkably good, resultsare ob- ,tained by making this block'of the material known commercially as cellugrap'h. This material consists of hardwood chemically treated to make it self lubricating and it'has a very low co efii'cientfof friction, exceptionally long life, and is'relativjely economical.

The construction illustrated at the right hand end of the crank arm 2 is the sameas that just described ez rc'ept that the, parts are slightly. smaller and 'the bea ring "block is" ,-of the solidtype instead 'of'being split. f

It will now" be appreciated that th's crank isy'relatively light in weight but is very sturdy and substantial in construction. Due to the peculiar nature of the design and the materials used it can. be manufactured'very economically and it has been demonstrated in actual practi'cefthat'it has 'a remarkably v long lifefev'en' under severe conditions of i service. Then a loom is ,stopp'ed'sudde'nly the longitudinal thrust'on the crank arm is very severe and 'itwiljl be observed that the construction shown is well adapted to with- I stand this thrust since the block 6 is seated on the shoulders l l, and also on the'bolt 8. The V-shap'e construction of'the groove and the extension from" the] block that is fs'eat'edin'it ofcourse exert a certain' tendency I to split the arm, but thistendency is eifectu ally resisted by the bolts 9 and 10 which 'squ'eezetheleg's ofthe strap 8 against'the opposite sides of'the'arm' 2.

'lhegrain of the wood in the arm 2 should run longitudinally of the arm and I prefer also to have the grain of the wood in the bearing block 6 run in this direction so that the thrust exerted on or by the wrist pin or cranlc pin will come on the end of the grain of the wood which withstands both deformation and wear more effectually than does the side of the grain. This arrangement, however, is not essential.

The construction shown in Figs. 3 and 4: comprises a crank arm 12 having a square shouldered groove 13 formed therethrough with flat shoulders 1 il l at opposite sides of this groove, and a bearing block 15 shaped to fit both the groove 18 and the shoulders 14:. A strap 16 extends around the end of the bearing block and is secured to the crank arm by a bolt 17. This bearing block has a hole 18 formed therethrough to receive a wrist pin or crank pin.

In this construction the groove 13 and the bolt 17 perform substantially the same functions that are performed by the groove 3 and bolt 10 in the construction above described. That is, they prevent relative lateral movement between the bearing block and crank arm in one direction and also prevent relative longitudinal movement of minor differences in the shape of the parts.

This construction has the same general advantages as those above mentioned in describing the form of the invention shown in Figs; 1 and 2. It should be noted that the bearing blocks can be very easily replaced whenever they become worn to such an extent that this is necessary, and since these parts can be manufactured very economically this replacement can be made at a trifling expense. I

An especially important advantage of the construction above described is that the bearing members are self-lubricating. I find that by using bearing blocks made of cellugraph a crank construction is obtained which is not only the equal in every respect of those heretofore used but is actually superior both in serviceability and ineconomy. The necessity for lubricating the bearing surfaces of crank arms of the character heretofore used has made these constructions very objectionable for loom work because of the liability to spot the yarn or goods with the lubricant used. Since my construction avoids the necessity for lubricating material, it eliminates not only this danger of damaging the goods being woven, but also the labor necessary to apply the lubricant properly and the expense for the lubricant itself.

lVhile l have herein described the forms of my invention which l consider at present to be preferable, it will be readily appreciated that these embodiments of the invention may be modified in minor particulars without departing from the spirit or scope of the invention,

Having thus described my invention what I desire to claim as new is:

1. .i device of the character described comprising, in combination, a crank arm grooved at one end, a bearing block seated in said groove, a strap fitting around the outer end of said block, and means for securing said strap to said arm whereby said strap secures said block in said groove.

2. A device of the character described comprising, in combination, a crank arm grooved at one end, a self-lubricating bearing block seated in said groove, a strap fitting around the outer end of said block, and a bolt securing said strap to said arm at opposite sides thereof.

3. A device of the character described comprising in combination, a crank arm, a self-lubricating bearing block having an interlocking engagement with one end of said arm' preventing relative lateral movement between said arm and block in one direction, and means for securing said block to said arm, said securing means preventing relative lateral movement between said block and arm at right angles to said direction and-also preventing movement of the block longitudinally away from the arm.

4. A device of the character described comprising, in combination, a crank arm, a wooden bearing block secured to one end of said arm and having a bearing surface formed therein, said end of the arm being grooved in a direction parallel to the axis of said bearing surface and having fiat shoulders at opposite sides of said groove,

said block having parts to fit said groove and shoulders, a strap fitting over one end of said block and extending along said arm,

at opposite sides thereof, and a bolt extending through said arm and strap and operative to secure said parts together and tending to squeeze said shoulders toward each other. v

5. A device of the character described comprising, in combination, a wooden crank arm having a V-shaped groove in one end thereof, a self-lubricating wooden bearing block seated in said groove, a strap fitting around the outer end of said block, and means securing said strap to said arm at opposite sides thereof.

6. A device of the character described comprising, in combination, a crank arm, a self-lubricating wooden bearing block mounted on one end of said arm, a strap fitting around the outer end of said block and extending baokwardly along said arm atopposite sides thereof, and means for securing said strap to said arm, said strap having a channel therein to receive said bearing block.

7. A device of the character described comprising, in combination, a crank arm having a groove in one end thereof With shoulders at opposite sides of said groove, a bearing block seated in said groove, a strap fitting around the outer end of said block and extending backwardly along said arm at opposite sides thereof, and tWo bolts securing said strap to said arm, one of said bolts having its axis located substantially in the plane of said shoulders. v

8. A device of the character described comprising, in combination, a crank arm grooved at one end, a bearing block seated in said groove, a strap fitting around theouter end of said block, and means for se curing said strap to sa1d arm, said strap and block having intereng'aging parts preventing movement of the block endvvise of said groove. I

9. A device of the character described comprising, in combination, a crank arm, a self-lubricating bearing block having interlocking connection with one end of said arm, a strap fitting around the outer end of said block, and means for securing the end portions of said strap to said arm.

CHARLESH. FIsH. 

